Well there are a few things I look for (I will produce a bonus video about this topic and add it to the other bonus video tutorial) but basically I like to see sites like forums/niche sites/Q&A sites in the top 10 along with other things like sites that are not targeting exact keyword in title/meta, sites with low page authority and domain authority, sites that are less than 3 years old etc etc
You can filter your results by 24 business verticals, including Apparel, Arts & Entertainment, Autos & Vehicles, Beauty & Fitness, Books & Literature, Business & Industrial, Computers & Electronics, Finance & Banking, Food & Drink, Toys & Games, Health, Hobbies & Leisure, Home & Garden, Internet & Telecom, Jobs & Education, Law & Government, News Media & Publications, Family & Community, Occasions & Gifts, Pets & Animals, Real Estate, Retail & General Merchandise, Sports & Fitness, and Travel & Tourism.
3. Finally, there's just good old research through trends and news. Google Trends, keeping up on industry news of the business, and even newsjacking (if there are relevant topics). These all require different resources depending on the business, but once you find the leaders in their news you can not only leverage them for keyword research but also glean insights into how you can become an industry leader yourself (and dominate SEO).
As for the history of the company, as I explained, I created Long Tail Pro back in 2011. At the time, I was creating tons of niche sites and was doing alot of keyword research and content creation. I was trying to figure out what types of keywords would rank quickly in the search engines, specifically Google, and I was frustrated with the other keyword research tools (in particular Market Samurai) out there.